This invention relates to apparatus for use in the vacuum-forming of sheet material in a mould.
In the art of vacuum forming sheet material, it is necessary to hold the sheet material securely on the mould as it is drawn down by the vacuum into the mould, but if the sheet material is held so firmly as to prevent any movement thereof, the sheet material is liable to be undesirably stretched or damaged, particularly if a deep mould is being used.
An object of the present invention is to provide improved apparatus designed to permit movement of the sheet material across the rim of the mould as the material is drawn into the mould but without permitting a substantial loss of vacuum.